1. Field of the Invention
The present invention relates to an endoscopic treatment instrument and a supporting adaptor to be used with an endoscope, and an endoscopic treatment system including the endoscope.
2. Description of the Related Art
An endoscopic treatment instrument (hereinafter, referred to as an instrument) is inserted into a body with an endoscope for carrying out a treatment for living organisms, and includes a distal treatment unit provided at a distal end of an elongated flexible sheath.
As the diameter of a forceps channel formed in the endoscope is small, the diameter of the instrument which can be inserted into the forceps channel is limited. Therefore, when a large sized instrument is to be used, an external channel can be provided outside an endoscope insertion part, and the sheath of the instrument is inserted through the external channel. The external channel extends substantially along the entire length of the endoscope insertion part. There is an endoscope of a type in which the external channel is fixed to the insertion part in such a manner that a wire is extended from a distal end portion of the external channel, a loop formed at a distal end of the wire is hooked to a distal end of the insertion part, and the external channel and the endoscope are engaged by a frictional force (for example, see JP-A-2002-143078).
There is also a type in which two of such external channels are mounted to the endoscope insertion part in parallel with each other, the sheath of the instrument is inserted into the external channels, and a needle of a suture instrument and a needle receiving unit are provided as a distal end treatment unit at a distal end of each sheath (for example, see the specification of U.S. patent application Publication No. 2003/0181924).
However, when a plurality of instruments are disposed along an outer surface of the endoscope insertion part for carrying out a treatment, in some cases, it may be effective to exchange the distal end treatment units between a left side and a right side (or between a upper side and a lower side) depending on conditions of an affected area and the direction of approach of the endoscope. In such cases, when the entire endoscope is rotated in order to exchange the distal end treatment units between the left side and the right side, the field of view of the endoscope is also rotated correspondingly, and hence it makes operation difficult for an operator.
In view of such circumstances, it is an object of the invention to enable treatment units at distal ends to be exchanged between left and right sides (or upper and lower sides) without rotating an endoscope.